<template>
    <div class="component-upload-image">
        <el-upload
                multiple
                :action="uploadImgUrl"
                list-type="picture-card"
                :on-success="handleUploadSuccess"
                :before-upload="handleBeforeUpload"
                :limit="limit"
                :on-error="handleUploadError"
                :on-exceed="handleExceed"
                ref="imageUpload"
                :before-remove="handleDelete"
                :show-file-list="true"
                :headers="headers"
                :file-list="fileList"
                :on-preview="handlePictureCardPreview"
                :class="{ hide: fileList.length >= limit }"
        >
            <el-icon class="avatar-uploader-icon">
                <plus/>
            </el-icon>
        </el-upload>
        <!-- 上传提示 -->
        <div class="el-upload__tip" v-if="showTip">
            请上传
            <template v-if="fileSize">
                大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b>
            </template>
            <template v-if="fileType">
                格式为 <b style="color: #f56c6c">{{ fileType.join("/") }}</b>
            </template>
            的文件
        </div>

        <el-dialog
                v-model="dialogVisible"
                title="预览"
                width="800px"
                append-to-body
        >
            <img
                    :src="dialogImageUrl"
                    style="display: block; max-width: 100%; margin: 0 auto"
             alt=""/>
        </el-dialog>
    </div>
</template>

<script setup>
import {getToken} from "@/utils/auth"

const props = defineProps({
    modelValue: [String, Object, Array],
    // 图片数量限制
    limit: {
        type: Number,
        default: 5,
    },
    // 大小限制(MB)
    fileSize: {
        type: Number,
        default: 5,
    },
    // 文件类型, 例如['png', 'jpg', 'jpeg']
    fileType: {
        type: Array,
        default: () => ["png", "jpg", "jpeg"],
    },
    // 是否显示提示
    isShowTip: {
        type: Boolean,
        default: true
    },
})

const {proxy} = getCurrentInstance()
const emit = defineEmits()
const number = ref(0)
const uploadList = ref([])
const dialogImageUrl = ref("")
const dialogVisible = ref(false)
const baseUrl = import.meta.env.VITE_APP_BASE_API
const uploadImgUrl = ref(import.meta.env.VITE_APP_BASE_API + "/common/upload") // 上传的图片服务器地址
const headers = ref({Authorization: "Bearer " + getToken()})
const fileList = ref([])
const showTip = computed(
    () => props.isShowTip && (props.fileType || props.fileSize)
)

watch(() => props.modelValue, val => {
    if (val) {
        // 首先将值转为数组
        const list = Array.isArray(val) ? val : props.modelValue.split(",")
        // 然后将数组转为对象数组
        fileList.value = list.map(item => {
            if (typeof item === "string") {
                if (item.indexOf(baseUrl) === -1) {
                    item = {name: baseUrl + item, url: baseUrl + item}
                } else {
                    item = {name: item, url: item}
                }
            }
            return item
        })
    } else {
        fileList.value = []
        return []
    }
}, {deep: true, immediate: true})

// 上传前loading加载
function handleBeforeUpload(file) {
    let isImg = false
    if (props.fileType.length) {
        let fileExtension = ""
        if (file.name.lastIndexOf(".") > -1) {
            fileExtension = file.name.slice(file.name.lastIndexOf(".") + 1)
        }
        isImg = props.fileType.some(type => {
            if (file.type.indexOf(type) > -1) return true
            return !!(fileExtension && fileExtension.indexOf(type) > -1)
        })
    } else {
        isImg = file.type.indexOf("image") > -1
    }
    if (!isImg) {
        proxy.$modal.msgError(
            `文件格式不正确, 请上传${props.fileType.join("/")}图片格式文件!`
        )
        return false
    }
    if (props.fileSize) {
        const isLt = file.size / 1024 / 1024 < props.fileSize
        if (!isLt) {
            proxy.$modal.msgError(`上传头像图片大小不能超过 ${props.fileSize} MB!`)
            return false
        }
    }
    proxy.$modal.loading("正在上传图片，请稍候...")
    number.value++
}

// 文件个数超出
function handleExceed() {
    proxy.$modal.msgError(`上传文件数量不能超过 ${props.limit} 个!`)
}

// 上传成功回调
function handleUploadSuccess(res, file) {
    if (res.code === 200) {
        uploadList.value.push({name: res.fileName, url: res.fileName})
        uploadedSuccessfully()
    } else {
        number.value--
        proxy.$modal.closeLoading()
        proxy.$modal.msgError(res.msg)
        proxy.$refs.imageUpload.handleRemove(file)
        uploadedSuccessfully()
    }
}

// 删除图片
function handleDelete(file) {
    const findex = fileList.value.map(f => f.name).indexOf(file.name)
    if (findex > -1 && uploadList.value.length === number.value) {
        fileList.value.splice(findex, 1)
        emit("update:modelValue", listToString(fileList.value))
        return false
    }
}

// 上传结束处理
function uploadedSuccessfully() {
    if (number.value > 0 && uploadList.value.length === number.value) {
        fileList.value = fileList.value.filter(f => f.url !== undefined).concat(uploadList.value)
        uploadList.value = []
        number.value = 0
        emit("update:modelValue", listToString(fileList.value))
        proxy.$modal.closeLoading()
    }
}

// 上传失败
function handleUploadError() {
    proxy.$modal.msgError("上传图片失败")
    proxy.$modal.closeLoading()
}

// 预览
function handlePictureCardPreview(file) {
    dialogImageUrl.value = file.url
    dialogVisible.value = true
}

// 对象转成指定字符串分隔
function listToString(list, separator) {
    let strs = ""
    separator = separator || ","
    for (let i in list) {
        if (undefined !== list[i].url && list[i].url.indexOf("blob:") !== 0) {
            strs += list[i].url.replace(baseUrl, "") + separator
        }
    }
    return strs !== "" ? strs.substr(0, strs.length - 1) : ""
}
</script>

<style scoped lang="scss">
// .el-upload--picture-card 控制加号部分
:deep(.hide .el-upload--picture-card) {
  display: none;
}
</style>
